“If you want to awaken all of Humanity, then awaken all of yourself,
if you want to eliminate the suffering in the world,
then eliminate all that is dark and negative in yourself.
Truly, the greatest gift you have to give is that of your own self-transformation.”

Note: According to a recent comment, the quote actually comes from a translation of another Taoist work called the Hua Hu Ching (Huahujing), which, although attributed to Lao Tzu, was actually written some 500 years after Lao Tzu lived, by Taoist Wang Fou.